• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.3D
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• pp.453-459
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• 2006

This paper presents an experimental evaluation of wandering effect on asphalt concrete pavement responses. A laser-based wandering system has been developed and its performance is verified under various field conditions. The portable wandering system composed of two laser sensors with Position Sensitive Devices can allow one to measure the distance between laser sensors and tire edges of moving vehicle. Therefore, lateral position of each wheel on the pavement can be determined in a real time manner. Pavement responses due to different loading paths are investigated using a roll over test which is carried out on one of asphalt surfaced pavements in the Korea Highway Corporation test road. The pavement section (A5) consists of 5 cm thick surface course; 7 cm intermediate course; and 18 mm base course, and is heavily instrumented with strain gauges, vertical soil pressure cells and thermo-couples. From the center of wheel paths, seven equally-spaced lateral loading paths are carefully selected over an 140 cm wandering zone. Test results show that lateral horizontal strains in both surface and intermediate courses are mostly compressive right under the loading path and tensile strains start to develop as the loading offset becomes 40 cm from the wheel path. The development of the vertical stresses in the top layers of subbase and anti-frost is found to be minimal once the loading offset becomes 50 cm.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.2
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• pp.180-187
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• 2010

The study was performed to investigate the property of rhizosphere microorganisms, and community structure during GMO, and Non-GMO rice cultivation. In the dilution plate technique, there were no significant differences in microbial populations of rhizosplane with genetically modified, and non-genetically modified rice cultivation, and rhizosphere were also the same results. Dominant bacterial genera were Afipia 12.5%, Spingomonas 10.0%, Ramlibacter 10.0%, Mycobacterium 7.5%, and Tetrasphaera 7.5% in rhizosphere soil of genetically modified rice plant, while Afipia 7.3%, Spingomonas 12.2%, Ramlibacter 7.3%, Mycobacterium 17.1%, Tetrasphaera 14.6% in non-genetically modified cultivated at Suwon test fields in 2006. Majorgenera isolated from root surface cultivated in Yesan fields were Arthrobacter 12.7% in rhizoplane of genetically modified plant, and Burkholderia 22.2% of non-genetically modified plant in 2007, Paucimonas 26.6% of genetically modified plant, Chryseobacterium 15.4% of non-genetically modified plant in 2008. Also the microbial communities in rhizosphere soils of genetically modified, and non-genetically modified plants were characterized using phospholipid fatty acid, and denaturing gradient gel electrophoresis. The phospholipid fatty acid profiles of soils in this condition showed different pattern, but did not show significant differences between soils cultivated with genetically or non-genetically modified rice plants.

• Aerospace Engineering and Technology
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• v.5 no.2
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• pp.67-76
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• 2006

This paper describes the analysis method to define the system specification for conducted EMI environment and verification method to evaluate the conducted EMI performance. Conducted EMI environment is characterized by the electrical power subsystem which is mainly issued by the switching circuit noise, common ground impedance coupling. To define and control these EMI problems, EMI assesment through system analysis are preceded at the early design phase and then EMI reduction methods are applied during the unit/system development phase. System EMC should be carefully controlled and designed in the consideration of EMC safety margin and its performance is fully evaluated at the whole development period.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.37 no.1
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• pp.58-62
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• 2000

We Propose modulation scheme using I-Q modulation for transmitting different information simultaneously. For transmitting 1bit of each information, we apply QPSK scheme, for more bits, MAPSK. At the second modulation stage, We mix PN wavefoms with APSK waveforms for spreading bandwith. BER(Bit Error Rate) of each Information of the proposed scheme is analyzed on computer simulation. Finally we show power spectrum before and after spreading bandwidth.

• Journal of the Korean GEO-environmental Society
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• v.15 no.2
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• pp.27-36
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• 2014

Due to the latitudinal location of Korea, the seasonally frozen ground has been focused on as research topics such as the frost heaving under the asphalt road rather than the permafrost ground. However, the recent construction of the second Korean Antarctic research station, the Jangbogo station and the participation on the development of the natural gas pipeline in Russia arouse the research interests on the behavior of the permafrost ground. At the design process of the geotechnical structures on the permafrost ground, the evaluation of the creep characteristics of the frozen soil is very crucial. Since the domestic specification on the frozen soil testing does not exist currently, it is necessary to evaluate the creep characteristics of frozen soils systematically with regard to the affecting factors. Therefore, the creep characteristics of the frozen specimens of dense Jumoonjin sand were evaluated under various loads at -5 and $-10^{\circ}C$. Based on the test results, as the load became close to the strength and the temperature became lower, the duration of the secondary creep became shorter and more distinct tertiary creep responses were observed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.4
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• pp.348-352
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• 1994

Soybean seed consists of two major storage protein, the 7S and 11S globulins. For improving the quality of soybean seed protein, an increase of 11S/7S ratio would be a desirable objective because the 11S globulin contains much more the sulfur-containing amino acids than the 7S globulin. In this study, some soybean varieties were used to investigate the analyzing method for 7S and 11S globulins. 7S and 11S globulins couble be fractionated by their different solubilities in tris buffers. Adjusting the pH and tris concentration were major factors affecting the precipitation of the two globulins. And it was possible to screen the soybean genotypes having aberrant subunit compositions of the two globulins by an sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of total soybean proteins. The ratio of 11S to 7S globulin ranged from 1.29 to 1.38. This paper also dealed with the contribution of protein components in soybean seeds to the physical properties of soycurd. It indicated that the soycurd from crude 11S was remarkably harder than that from crude 7S, and springiness and cohesiveness were slightly higher in soycurd having higher proportion of 11S. So, it may concluded that proportion of protein components in soybean seed can be important factor which controls the suitability for soycurd or other foods.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.4
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• pp.47-54
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• 2010

This study is progressed function ratio, it's trued taste by an experiment to present data for human work light weight aggregate development that use clink ash progressed liquid limit, small success limit, wear loss in quantity, sand equivalent, sieve cutting examination. 80:20's match of function rain examination is 1.4, and that use rubble aggregate as recyeled-panit lightweight aggregate's capacity ratio increases by 1.0 increase of function rain many. Also, examination multiplied delicate flavor gradually according to increase of the mixing rate, and absorption coefficient increased. This is judged by phenomenon that appear by special quality upper recycled-panit of polystyrene bid and porosity's increase between lightweight aggregate. It is case that use aggregate of wear loss in quantity is 13.5 in sand equivalent and a wear loss in quantity experiment and although case that mix 20% increases by 14.4, this phenomenon by weak tissue of lightweight aggergate be judged. When it's as a these experiment, the statue prevention floor of a street improvement specifications is prescribing so that satisfy by sand equivalent 20, CBR 10. This is showed result that this satisfies in quality standard all in match experiment ago that see.

• Fire Science and Engineering
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• v.23 no.6
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• pp.116-125
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• 2009

This study is progressed function ratio, it's trued taste by an experiment to present data for human work light weight aggregate development that use clink ash progressed liquid limit, small success limit, wear loss in quantity, sand equivalent, sieve cutting examination. 80 : 20's match of function rain examination is 1.4, and that use rubble Goljae as ckink ash lightweight aggregate's capacity ratio increases by 1.0 increase of function rain many. Also, examination multiplied delicate flavor gradually according to increase of the mixing rate, and absorption coefficient increased. This is judged by phenomenon that appear by special quality upper clink ash of polystyrene bid and porosity's increase between lightweight aggregate. It is case that use aggregate of wear loss in quantity is 13.5 in sand equivalent and a wear loss in quantity experiment and although case that mix 20% increases by 14.4, this phenomenon by weak tissue of lightweight aggergate be judge. When it's as a these experiment, the statue prevention floor of a street improvement specifications is prescribing so that satisfy by sand equivalent 20, CBR 10. This is showed result that this satisfies in quality standard all in match experiment ago that see.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2012.05a
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• pp.16-16
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• 2012

야콘의 국내 새로운 소득 작목으로 도입하고자 재배 면적, 농가 수 등의 재배 동향을 조사 분석하였다. 야콘은 국화과의 다년생 초본식물로서 땅속에서 붉은 구슬 모양 관아로 번식한다. 땅속의 덩이뿌리인 괴근은 고구마와 비슷하고 잎줄기는 해바라기와 흡사하다. 다년생 초본으로 분류되지만 우리나라처럼 초겨울에 동상해가 자주 발생하는 곳에서는 식물체가 고사하기 쉬우므로 일년생으로 재배하기도 한다. 야콘은 배처럼 아삭아삭 씹히며 단맛이 있고 수분이 많아 시원함을 주는데 열을 가하여 조리하면 연근 같은 맛이 난다. 우리나라의 야콘은 농촌진흥청에 의해 1985년에 처음으로 도입되어 1986년과 1987년에 시험연구를 거쳐 강원 충북 경북 등의 농가에 최초로 보급되었다. 야콘이 도입된 초창기에는 재배 방법이 확립되지 않아 널리 재배되지 못하였다. 최근 10년간 야콘의 재배 면적과 재배 농가 수는 급격하게 늘어났다. 1999년에는 상주 영주 강릉 강화 등의 일부 지역의 10여 농가에서 8ha정도 재배하였으나, 2009년에는 447농가, 166ha로 각각 약 45배, 20배씩 증가하였다. 지역별 재배 면적은 경북 59ha(35%), 강원 30ha(18%), 경기 20ha(12%)로 경북, 강원, 경기의 순이었다. 재배 농가 수는 서울에서 가까운 경기도 지역이 117개 농가(26%)로 가장 많았고, 강원 69개 농가(15%), 경북 54개 농가(12%)로 경기, 강원, 경북의 순이었다. 야콘 재배농가의 경력은 평균 7년이었으며, 특히 2000년 이후 재배를 시작한 농가가 전체의 68%로 야콘 재배가 최근 들어 증가하고 있음을 알 수 있었다. 단위면적당 수량은 5,506kg/10a으로서 감자나 고구마보다 2~3배 많았다. 소득은 2,041천 원/10a으로 감자와 고구마에 비해 두 배 이상 높은 것으로 조사되었다.

• Journal of the Korean Geosynthetics Society
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• v.9 no.3
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• pp.39-45
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• 2010

When the ground temperature drops below $0^{\circ}C$, wet soils expand due to the ice formation in their porous space. This results in frost heave which causes structural stability problems. Frost heave is attributed by several factors such as physical soil properties and heat transfer including pore water phase change. Due to the complex physical phenomena, reliable and verified multi-dimensional numerical models for frost heave problems are still in a research stage. This study presents an efficient and simple method of overcoming numerical problems associated with sudden jump of heat capacity due to the phase change from water to ice in the pore space. This paper proposes heat transfer equation and finite element method when the saturated soils or porous rocks are subjected to freezing. Numerical analyses using the proposed method agree well with the known closed form solution and the laboratory test results.